On 14.11.2013 18:03, M A Young wrote:
> 
> 
> On Thu, 14 Nov 2013, M A Young wrote:
> 
>> On Wed, 13 Nov 2013, Vladimir 'φ-coder/phcoder' Serbinenko wrote:
>>
>>> On 13.11.2013 20:06, M A Young wrote:
>>>> It doesn't seem to understand sub-partitions. I can get it to work if
>>>> the boot files are in /dev/xvda but not in /dev/xvda1 .
>>>>
>>> insmod part_msdos
>>> insmod part_gpt
>>
>> Right, if I add those to the embedded grub.cfg file I get to the
>> standard grub menu and the boot starts. However the boot doesn't get
>> very far - it loads the kernel and the initrd file and starts the
>> kernel but the kernel doesn't see the virtual disks so it doesn't get
>> very far.
> 
> Using xenstore-ls from the dom0 on the guest when the boot stops the
> local/domain/2/device/vbd/51712 section looks like
>       backend = "/local/domain/0/backend/vbd/2/51712"
>       backend-id = "0"
>       state = "6\000"
>       virtual-device = "51712"
>       device-type = "disk"
>       ring-ref = "\000"
>       event-channel = "\000"
>       protocol = "x86_64-abi\000"
> 
> As nothing else has null character endings I suspend that is wrong.
> 
Good catch. Could you test following:
diff --git a/grub-core/kern/xen/init.c b/grub-core/kern/xen/init.c
index 3bfd99f..ab74543 100644
--- a/grub-core/kern/xen/init.c
+++ b/grub-core/kern/xen/init.c
@@ -256,11 +256,10 @@ grub_xenstore_write_file (const char *dir, const void *buf, grub_size_t len)
 
   grub_memset (&msg, 0, sizeof (msg));
   msg.type = XS_WRITE;
-  msg.len = dirlen + len + 1;
+  msg.len = dirlen + len;
   grub_xen_store_send (&msg, sizeof (msg));
   grub_xen_store_send (dir, dirlen);
   grub_xen_store_send (buf, len);
-  grub_xen_store_send ("", 1);
   grub_xen_store_recv (&msg, sizeof (msg));
   resp = grub_malloc (msg.len + 1);
   if (!resp)

>     Michael Young